title: Attenuated hypocholesterolemia following severe trauma signals risk for late ventilator-associated pneumonia, ventilator dependency, and death: a retrospective study of consecutive patients.
abstract: BACKGROUND
  Post-traumatic ventilator-associated pneumonia (VAP) is a substantial clinical problem that increases hospital costs and typically adds to the duration of mechanical ventilation. We evaluated the impact of VAP on ventilator days. We also assessed 48-hour total blood cholesterol (TC) and other potential risk factors for the development of VAP.
  
  
  METHODS
  We performed a retrospective study of consecutive trauma patients requiring emergency tracheal intubation and evaluated TC, age, gender, ethanol status, smoker status, injury mechanism, chest injury, brain injury, Injury Severity Score (ISS), shock, day-one hypoxemia, and RBC transfusion as potential risks for VAP.
  
  
  RESULTS
  The 152 patients had ISS 28.1, brain injury 68.4%, VAP 50.0%, ventilator days 14.3, and death 9.9%. Ventilator days were increased with late VAP (p < 0.0001). TC was 110.7 mg/dL with expected TC 197.5 mg/dL. TC was lower with chest injury, shock, and RBC transfusion but, higher with brain injury (p ≤ 0.01). TC decreased as ISS increased (p = 0.01). However, one patient subset (ISS ≥ 20-&-TC ≥ 90 mg/dL) had a relative increase in TC despite an increase in ISS. ISS ≥ 20-&-TC ≥ 90 mg/dL, but not ISS alone, was the only independent predictor of late VAP (OR 3.0; p = 0.002). ISS ≥ 20-&-TC ≥ 90 mg/dL and day-one hypoxemia were the only independent predictors for increased ventilator days (p = 0.01). ISS ≥ 20-&-TC ≥ 90 mg/dL, but not ISS alone, was the only predictor of death (OR 3.8; p = 0.03).
  
  
  CONCLUSIONS
  Severe traumatic injury produced substantial hypocholesterolemia that is greater with chest injury, shock, and RBC transfusion, but less with brain injury. Total blood cholesterol tended to decrease with increasing injury severity. However, attenuated hypocholesterolemia (ISS ≥ 20-&-TC ≥ 90 mg/dL) represents a unique response that can occur with critical injury. Attenuated hypocholesterolemia signals early risk for late VAP, ventilator dependency, and death.
authors.affiliation: Trauma/Critical Services, St. Elizabeth Health Center, 1044 Belmont Avenue, Youngstown, OH 44501, USA. dunham.michael@sbcglobal.net
authors.forename: C Michael
authors.initials: CM
authors.lastname: Dunham
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Chirichella
mesh_terms: D002784:Cholesterol / Q000097:blood*; D017707:Erythrocyte Transfusion / Q000009:adverse effects; D006801:Humans; D015601:Injury Severity Score; D007442:Intubation, Intratracheal / Q000009:adverse effects; D007902:Length of Stay; D053717:Pneumonia, Ventilator-Associated / Q000209:etiology* / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors; D012769:Shock / Q000150:complications; D013898:Thoracic Injuries / Q000150:complications; D015300:Ventilator Weaning; D012122:Ventilators, Mechanical / Q000009:adverse effects*; D014947:Wounds and Injuries / Q000150:complications* / Q000401:mortality
chemical_list: D002784:Cholesterol